The commit 16116dac23 ("batman-adv: prevent TT request storms by not
sending inconsistent TT TLVLs") added checks to the local (direct) TT
response code. But the response can also be done indirectly by another node
using the global TT state. To avoid such inconsistency states reported in
the original fix, also avoid sending empty VLANs for replies from the
global TT state.
Cc: stable@kernel.org
Fixes: 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN specific")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
The local TT based TVLV is generated by first checking the number of VLANs
which have at least one TT entry. A new buffer with the correct size for
the VLANs is then allocated. Only then, the list of VLANs s used to fill
the VLAN entries in the buffer. During this time, the meshif_vlan_list_lock
is held. But the actual number of TT entries of each VLAN can still
increase during this time - just not the number of VLANs in the list.
But the prefilter used in the buffer size calculation might still cause an
increase of the number of VLANs which need to be stored. Simply because a
VLAN might now suddenly have at least one entry when it had none in the
pre-alloc check - and then needs to occupy space which was not allocated.
It is better to overestimate the buffer size at the beginning and then fill
the buffer only with the VLANs which are not empty.
Cc: stable@kernel.org
Fixes: 16116dac23 ("batman-adv: prevent TT request storms by not sending inconsistent TT TLVLs")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
batadv_piv_tt::last_changeset_len len was declared as s16, but the field is
never intended to hold a negative value. When a value greater than 32767 is
assigned, it wraps to a negative signed integer.
In batadv_send_my_tt_response(), last_changeset_len is temporarily widened
to s32. The incorrectly negative s16 value propagates into the s32, causing
batadv_tt_prepare_tvlv_local_data() to allocate a full sized buffer but
populates only a small portion of it with the collected changeset. All
remaining bits are kept uninitialized.
Using an u16 avoids this type confusion and ensures that no (negative) sign
extension is performed in batadv_send_my_tt_response().
Cc: stable@kernel.org
Fixes: a73105b8d4 ("batman-adv: improved client announcement mechanism")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
batadv_orig_node::tt_buff_len was declared as s16, but the field is never
intended to hold a negative value. When a value greater than 32767 is
assigned, it wraps to a negative signed integer.
In batadv_send_other_tt_response(), tt_buff_len is temporarily widened to
s32. The incorrectly negative s16 value propagates into the s32, causing
batadv_tt_prepare_tvlv_global_data() to allocate a full sized buffer but
populates only a small portion of it with the collected changeset. All
remaining bits are kept uninitialized.
Using an u16 avoids this type confusion and ensures that no (negative) sign
extension is performed in batadv_send_other_tt_response().
Cc: stable@kernel.org
Fixes: a73105b8d4 ("batman-adv: improved client announcement mechanism")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
The commit 3a359bf5c6 ("batman-adv: reject oversized global TT response
buffers") added a check to ensure that a global return buffer size can be
stored in an u16. The same buffer handling also exists for the local data
buffer but was not touched.
A similar check should be also be in place for the local TVLV buffer. It
doesn't have the similar attack surface because it is only generated from
locally discovered MAC addresses but the dynamic nature could still cause
temporarily to large buffers.
Cc: stable@kernel.org
Fixes: 7ea7b4a142 ("batman-adv: make the TT CRC logic VLAN specific")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Four sysfs show() callbacks in hv-gpci take get_cpu_var(hv_gpci_reqb)
(which calls preempt_disable()) but only call the matching put_cpu_var()
on the error path under the 'out:' label. Every successful read leaks
one preempt_disable():
processor_bus_topology_show()
processor_config_show()
affinity_domain_via_virtual_processor_show()
affinity_domain_via_domain_show()
(affinity_domain_via_partition_show() was already correct.)
On a CONFIG_PREEMPT=y kernel, repeated reads raise preempt_count and
eventually return to userspace with preemption still disabled. The
next user-mode page fault then hits faulthandler_disabled() == 1,
gets forced to SIGSEGV, and the resulting coredump trips
'BUG: scheduling while atomic' in call_usermodehelper_exec ->
wait_for_completion_state -> schedule:
BUG: scheduling while atomic: <task>/<pid>/0x00000004
...
__schedule_bug+0x6c/0x90
__schedule+0x58c/0x13a0
schedule+0x48/0x1a0
schedule_timeout+0x104/0x170
wait_for_completion_state+0x16c/0x330
call_usermodehelper_exec+0x254/0x2d0
vfs_coredump+0x1050/0x2590
get_signal+0xb9c/0xc80
do_notify_resume+0xf8/0x470
Add an out_success label that calls put_cpu_var() before returning
the byte count, mirroring affinity_domain_via_partition_show().
Fixes: 71f1c39647 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show processor bus topology information")
Fixes: 1a160c2a13 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show processor config information")
Fixes: 71a7ccb478 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show affinity domain via virtual processor information")
Fixes: a69a57cac1 ("powerpc/hv_gpci: Add sysfs file inside hv_gpci device to show affinity domain via domain information")
Signed-off-by: Aboorva Devarajan <aboorvad@linux.ibm.com>
Reviewed-by: Ritesh Harjani (IBM) <ritesh.list@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260508041256.3447113-1-aboorvad@linux.ibm.com
The GUEST_STATE_BUFFER_TEST config option should default
to KUNIT_ALL_TESTS so that if all tests are enabled then
it is included, but currently the 'default KUNIT_ALL_TESTS'
statement is shadowed by 'def_tristate n',
meaning that this second default statement is currently dead code.
It looks to me like the commit
6ccbbc33f0 ("KVM: PPC: Add helper library for Guest State Buffers")
intended to set the default to KUNIT_ALL_TESTS, but mistakenly
missed the def_tristate.
This dead code was found by kconfirm, a static analysis tool for Kconfig.
Fixes: 6ccbbc33f0 ("KVM: PPC: Add helper library for Guest State Buffers")
Signed-off-by: Julian Braha <julianbraha@gmail.com>
Tested-by: Gautam Menghani <gautam@linux.ibm.com>
Reviewed-by: Amit Machhiwal <amachhiw@linux.ibm.com>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260405161545.161006-1-julianbraha@gmail.com
Commit a28d3af2a2 ("[PATCH] 2/5 powerpc: Rework PowerMac i2c part 2")
removed the last calls to the pmac_low_i2c_{lock,unlock}() functions.
Hence, remove these two functions.
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260316174747.3871924-1-bvanassche@acm.org
pika_dtm_thread() acquires client through of_find_i2c_device_by_node()
but fails to release it in error handling path. This could result in a
reference count leak, preventing proper cleanup and potentially
leading to resource exhaustion. Add put_device() to release the
reference in the error handling path.
Found by code review.
Cc: stable@vger.kernel.org
Fixes: 3984114f05 ("powerpc/warp: Platform fix for i2c change")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20251116024411.21968-1-make24@iscas.ac.cn
Uninitialized pointers with `__free` attribute can cause undefined
behavior as the memory allocated to the pointer is freed automatically
when the pointer goes out of scope.
powerpc/km82xx doesn't have any bugs related to this as of now, but,
it is better to initialize and assign pointers with `__free` attribute
in one statement to ensure proper scope-based cleanup
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/aPiG_F5EBQUjZqsl@stanley.mountain/
Signed-off-by: Ally Heev <allyheev@gmail.com>
Fixes: 4aa5cc1e00 ("powerpc-km82xx.c: replace of_node_put() with __free")
Reviewed-by: Christophe Leroy (CS GROUP) <chleroy@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20251116-aheev-uninitialized-free-attr-km82xx-v2-1-4307e2b5300d@gmail.com
The G5 defconfig is clearly intended for the G5 Powermac
series, and that should enable all the available
windfarm drivers, or the machine will overheat a short
while after booting and shut itself down, which is
annoying.
Signed-off-by: Linus Walleij <linusw@kernel.org>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20260505-powermac-g5-config-v3-1-7747bf72f874@kernel.org
Make sure resources are not improperly shared in the op cache and
cause instruction corruption this way.
Signed-off-by: Prathyushi Nangia <prathyushi.nangia@amd.com>
Co-developed-by: Borislav Petkov (AMD) <bp@alien8.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
imx8qxp_pxl2dpi_get_available_ep_from_port() returns ERR_PTR()
on errors. imx8qxp_pxl2dpi_find_next_bridge() stores its return
value in a __free(device_node) variable before checking IS_ERR().
When the function returns on the error path, the cleanup action calls
of_node_put() on the ERR_PTR() value.
Do not let a device_node cleanup variable hold error pointers. Change
imx8qxp_pxl2dpi_get_available_ep_from_port() to return an int and pass
the endpoint node through an output argument. Initialize the output
argument to NULL so callers hold either NULL on error paths or a valid
device_node pointer on successful path.
Fixes: ceea3f7806 ("drm/bridge: imx8qxp-pxl2dpi: simplify put of device_node pointers")
Cc: stable@vger.kernel.org
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Link: https://patch.msgid.link/20260507100604.667731-1-lgs201920130244@gmail.com
Signed-off-by: Liu Ying <victor.liu@nxp.com>
In cs35l56_dsp_work() check that the request for runtime-resume was
successful instead of assuming that it can't fail.
We may as well do this using the new PM_RUNTIME_ACQUIRE*() macros and
remove the manual pm_runtime_put_autosuspend() and associated gotos.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20260511114239.44970-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
The smn_read_register() helper returns negative error codes on failure
or the register value on success. When used with read_poll_timeout(),
the return value is stored in the 'data' variable.
Currently 'data' is declared as u32, which causes negative error codes
to be cast to large positive values. This makes the condition 'data > 0'
incorrectly treat errors as success.
Fix by changing 'data' from u32 to int, matching the pattern used in
psp_mbox_ready() which correctly handles the same helper function.
Reported-by: Dan Carpenter <error27@gmail.com>
Closes: https://lore.kernel.org/linux-sound/agGES8vWrLOrBu28@stanley.mountain/
Fixes: f120cf33d2 ("ASoC: SOF: amd: Use AMD_NODE")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20260511153638.724810-1-mario.limonciello@amd.com
Signed-off-by: Mark Brown <broonie@kernel.org>
In qed_init_wfq_param(), variable non_requested_count can become zero
when the number of vports with the configured flag set (including the
current vport being configured) equals total num_vports. This happens
when configuring the last unconfigured vport or when re-configuring
an already configured vport.
The function then calculates left_rate_per_vp = total_left_rate /
non_requested_count, which causes division by zero.
Fix this by skipping the division when non_requested_count is zero.
In that case, there is no remaining bandwidth to distribute, so just
record the configuration for the current vport and return success.
Fixes: bcd197c81f ("qed: Add vport WFQ configuration APIs")
Signed-off-by: Evgenii Burenchev <evg28bur@yandex.ru>
Link: https://patch.msgid.link/20260507145520.23106-1-evg28bur@yandex.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
On Glymur, all QMP PHYs except the one used by USB SS0 take their
reference clock from the TCSR clock controller. Since these TCSR clocks
already derive from RPMH_CXO_CLK as their sole parent, there is no need
to provide an extra `clkref` clock to the PHY nodes.
Drop the extra RPMh CXO clock inputs and use the TCSR clocks as the PHY
reference clocks instead.
This also fixes the devicetree schema validation, as the bindings do not
allow a separate `clkref` clock.
Fixes: 4eee57dd4d ("arm64: dts: qcom: glymur: Add USB related nodes")
Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Reported-by: Rob Herring <robh@kernel.org>
Closes: https://lore.kernel.org/r/20260410145205.GA554754-robh@kernel.org/
Signed-off-by: Abel Vesa <abel.vesa@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260414-dts-glymur-drop-rpmh-cxo-clk-from-qmpphys-v1-1-ab12d77c4aec@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
lockdep_sock_is_held() was added in tcp_ao_established_key()
by the cited commit.
It can be called from tcp_v[46]_timewait_ack() with twsk.
Since it does not have sk->sk_lock, the lockdep annotation
results in out-of-bound access.
$ pahole -C tcp_timewait_sock vmlinux | grep size
/* size: 288, cachelines: 5, members: 8 */
$ pahole -C sock vmlinux | grep sk_lock
socket_lock_t sk_lock; /* 440 192 */
Let's not use lockdep_sock_is_held() for TCP_TIME_WAIT.
Fixes: 6b2d11e2d8 ("net/tcp: Add missing lockdep annotations for TCP-AO hlist traversals")
Reported-by: Damiano Melotti <melotti@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20260508120853.4098365-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ena_phc_gettimex64() is setting the output parameter regardless
of whether ena_com_phc_get_timestamp() succeeded or failed.
When ena_com_phc_get_timestamp() returns an error, the timestamp
parameter may contain uninitialized stack memory (e.g., when PHC is
disabled or in blocked state) or invalid hardware values. Passing
these to userspace via the PTP ioctl is both a security issue
(information leak) and a correctness bug.
Fix by checking the return code after releasing the lock and only
setting the output timestamp on success.
Fixes: e0ea34158e ("net: ena: Add PHC support in the ENA driver")
Cc: stable@vger.kernel.org
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Reviewed-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20260507003518.22554-1-akiyano@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When iov_iter_get_pages2() fails in rds_message_zcopy_from_user(),
the pinned pages are released with put_page(), and
rm->data.op_mmp_znotifier is cleared. But we fail to properly
clear rm->data.op_nents.
Later when rds_message_purge() is called from rds_sendmsg() the
cleanup loop iterates over the incorrectly non zero number of
op_nents and frees them again.
Fix this by properly resetting op_nents when it should be in
rds_message_zcopy_from_user().
Fixes: 0cebaccef3 ("rds: zerocopy Tx support.")
Signed-off-by: Allison Henderson <achender@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20260505234336.2132721-1-achender@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Chuanhua Lei's email address has been bouncing for months. Remove the entry
and mark the PCI intel-gw driver as orphaned.
Signed-off-by: Florian Eckert <fe@dev.tdt.de>
Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://patch.msgid.link/20260417-pcie-intel-gw-v5-1-0a2b933fe04f@dev.tdt.de
In zonefs the file name in one of the two directories corresponds to the
zone number.
Here Alexey reported a possible integer overflow in zonefs_fname_to_fno(),
where the parsing of the zone number from the file name can overflow the
'long' data type.
Add a check for integer overflows and if the fno 'long' did overflow
return -ENOENT.
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Fixes: d207794aba ("zonefs: Dynamically create file inodes when needed")
Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Fix to decouple KUNIT_DEBUGFS and KUNIT_ALL_TESTS options and fix
KUNIT_DEBUGFS dependencies so it depends on DEBUG_FS without which
it will not be useful.
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Merge tag 'linux_kselftest-kunit-fixes-7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kunit fixes from Shuah Khan:
"Fix to decouple KUNIT_DEBUGFS and KUNIT_ALL_TESTS options and fix
KUNIT_DEBUGFS dependencies so it depends on DEBUG_FS without which it
will not be useful"
* tag 'linux_kselftest-kunit-fixes-7.1-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: config: KUNIT_DEBUGFS should depend on DEBUG_FS
kunit: config: Enable KUNIT_DEBUGFS by default
In scx_root_enable_workfn(), put_task_struct(p) is called before scx_error()
dereferences p->comm and p->pid. If the iterator's reference is the last
drop, the task is freed synchronously and the deref becomes a UAF.
Move put_task_struct() past scx_error().
Reported-by: Sashiko <sashiko-bot@kernel.org>
Closes: https://lore.kernel.org/all/20260511214031.AF5E9C2BCB0@smtp.kernel.org/
Fixes: f0e1a0643a ("sched_ext: Implement BPF extensible scheduler class")
Cc: stable@vger.kernel.org # v6.12+
Signed-off-by: Tejun Heo <tj@kernel.org>
gfx_v12_0_init_microcode() always loads RS64 CP ucode but never set
adev->gfx.rs64_enable, so it stayed false and code that branches on it
(e.g. MEC pipe reset) used the legacy CP_MEC_CNTL path incorrectly.
Match GFX11: derive RS64 mode from the PFP firmware header (v2.0) via
amdgpu_ucode_hdr_version(). Log at debug when RS64 is enabled.
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Jesse Zhang <jesse.zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit b03d53598b)
The legacy CPER debugfs reader can reach the payload path without a
valid pointer snapshot. The remaining user byte count is also treated as
the ring occupancy in dwords, so reads past the header can copy more than
requested.
Take the CPER lock before sampling pointers. Resample rptr/wptr for
payload reads, bound the payload copy by available dwords and the
remaining user size, and advance the file position for each dword copied.
Signed-off-by: Xiang Liu <xiang.liu@amd.com>
Reviewed-by: Tao Zhou <tao.zhou1@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1e40ef87ff)
[Why]
dcn32_validate_bandwidth() wraps dcn32_internal_validate_bw() with
DC_FP_START()/DC_FP_END(). In x86 non-RT, DC_FP_START takes fpregs_lock(),
which disables local softirqs.
The DML1 path through dcn32_enable_phantom_plane() calls kvzalloc() to
allocate ~335 KiB for dc_plane_state. This triggers the vmalloc path,
which calls BUG_ON(in_interrupt()) because it's invoked within the
FPU-enabled (softirq disabled) region, leading to a kernel crash.
[How]
Wrap the dc_state_create_phantom_plane() call with the
DC_RUN_WITH_PREEMPTION_ENABLED() macro to allow preemption during
this memory allocation.
Fixes: 235c676342 ("drm/amd/display: add DCN32/321 specific files for Display Core")
Closes: https://gitlab.freedesktop.org/drm/amd/-/work_items/4470
Reviewed-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: James Lin <pinglei.lin@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 885ccbef7b)
Cc: stable@vger.kernel.org
Fix lock inversions pointed out by Prike and Sunil. The hang detection
timeout *CAN'T* grab locks under which we wait for fences, especially
not the userq_mutex lock.
Then instead of this completely broken handling with the
hang_detect_fence just cancel the work when fences are processed and
re-start if necessary.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Sunil Khatri <sunil.khatri@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1b62077f04)
Well the reset handling seems broken on multiple levels.
As first step of fixing this remove most calls to the hang detection.
That function should only be called after we run into a timeout! And *NOT*
as random check spread over the code in multiple places.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Sunil Khatri <sunil.khatri@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 71bea36b54)
This one was fortunately not looking so bad as the wait ioctl path, but
there were still a few things which could be fixed/improved:
1. Allocating with GFP_ATOMIC was quite unnecessary, we can do that
before taking the userq_lock.
2. Use a new mutex as protection for the fence_drv_xa so that we can do
memory allocations while holding it.
3. Starting the reset timer is unnecessary when the fence is already
signaled when we create it.
4. Cleanup error handling, avoid trying to free the queue when we don't
even got one.
v2: fix incorrect usage of xa_find, destroy the new mutex on error
v3: cleanup ref ordering
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Sunil Khatri <sunil.khatri@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 1609eb0f81)
The purpose of a GPU reset is to make sure that fence can be signaled
again and the signal and resume workers can make progress again.
So waiting for the resume worker or any fence in the GPU reset path is
just utterly nonsense.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Prike Liang <Prike.Liang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit fcd5f065ea)
Retry doesn't work here, since bo will be freed on error, leading to
UAF. However, now that we do the alloc & init before the attach, we can
now combine this as one unit and have the init do the alloc for us. This
should make the retry safe.
Reported by Sashiko.
v2: Fix up the error unwind (CI)
Closes: https://sashiko.dev/#/patchset/20260506184332.86743-2-matthew.auld%40intel.com
Fixes: eb289a5f6c ("drm/xe: Convert xe_dma_buf.c for exhaustive eviction")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org> # v6.18+
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20260508102635.149172-4-matthew.auld@intel.com
(cherry picked from commit 4796694182)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
There look to be some nasty races here when triggering the
invalidate_mappings hook:
1) We do xe_bo_alloc() followed by the attach, before the actual full bo
init step in xe_dma_buf_init_obj(). However the bo is visible on the
attachments list after the attach. This is bad since exporter driver,
say amdgpu, can at any time call back into our invalidate_mappings hook,
with an empty/bogus bo, leading to potential bugs/crashes.
2) Similar to 1) but here we get a UAF, when the invalidate_mappings
hook is triggered. For example, we get as far as xe_bo_init_locked()
but this fails in some way. But here the bo will be freed on error, but
we still have it attached from dma-buf pov, so if the
invalidate_mappings is now triggered then the bo we access is gone and
we trigger UAF and more bugs/crashes.
To fix this, move the attach step until after we actually have a fully
set up buffer object. Note that the bo is not published to userspace
until later, so not sure what the comment "Don't publish the bo
until we have a valid attachment", is referring to.
We have at least two different customers reporting hitting a NULL ptr
deref in evict_flags when importing something from amdgpu, followed by
triggering the evict flow. Hit rate is also pretty low, which would
hint at some kind of race, so something like 1) or 2) might explain
this.
v2:
- Shuffle the order of the ops slightly (no functional change)
- Improve the comment to better explain the ordering (Matt B)
Assisted-by: Gemini:gemini-3 #debug
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/7903
Link: https://gitlab.freedesktop.org/drm/xe/kernel/-/work_items/4055
Fixes: dd08ebf6c3 ("drm/xe: Introduce a new DRM driver for Intel GPUs")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: <stable@vger.kernel.org> # v6.8+
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://patch.msgid.link/20260508102635.149172-3-matthew.auld@intel.com
(cherry picked from commit af1f2ad0c5)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
The blitter engines' MEM_COPY and MEM_SET instructions were added as
part of the same hardware change that introduced service copy engines
(i.e., BCS1-BCS8) which is why the driver checks for service copy engine
presence when deciding whether to use these instructions or the older
XY_* instructions. However when making this decision the driver should
consider which engines are part of the hardware architecture, not which
engines are present/usable on the current device. For graphics IP
versions that architecturally include service copy engines (i.e.,
everything Xe2 and later, plus PVC's Xe_HPC) we should use MEM_SET and
MEM_COPY even in if all of the service copy engines wind up getting
fused off. I.e., we need to decide based on whether the platform's
graphics descriptor contains these engines, rather than whether the
usable engine mask contains them. This logic got broken when
gt->info.__engine_mask was removed, although in practice that mistake
has been harmless so far because there haven't been any hardware
SKUs that fuse off all of the service copy engines yet.
Replace the incorrect has_service_copy_support() function with a GT
feature flag that tracks more accurately whether the new blitter
instructions are usable. In addition to fixing incorrect logic if all
service copies are fused off, the flag also makes it more obvious what
the calling code is trying to do; previously it wasn't terribly obvious
why "has service copy engines" was being used as the condition for using
different instructions on all copy engine types.
The new feature flag is named 'has_xe2_blt_instructions' because we
expect this flag to be set for all Xe2 and later platforms (i.e.,
everything officially supported by the Xe driver). Technically there's
also one Xe1-era platform (PVC) that supports these engines/instructions
and will set this flag, but this still seems to be the most clear and
understandable name for the flag.
Fixes: 61549a2ee5 ("drm/xe: Drop __engine_mask")
Cc: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Reviewed-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Link: https://patch.msgid.link/20260507-xe2_copy-v1-1-26506381b821@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
(cherry picked from commit 09b3998429)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
xe_bo_recompute_purgeable_state() walks all VMAs of a BO to determine
whether the BO can be made purgeable. This makes VMA create/destroy and
madvise updates O(n) in the number of mappings.
Replace the walk with BO-local counters protected by the BO dma-resv
lock:
- vma_count tracks the number of VMAs mapping the BO.
- willneed_count tracks active WILLNEED holders, including WILLNEED
VMAs and active dma-buf exports for non-imported BOs.
A DONTNEED BO is promoted back to WILLNEED on a 0->1 transition of
willneed_count. A BO is demoted to DONTNEED on a 1->0 transition only
when it still has VMAs, preserving the previous behaviour where a BO
with no mappings keeps its current madvise state.
PURGED remains terminal, preserving the existing "once purged, always
purged" rule.
Fixes: 4f44961eab ("drm/xe/vm: Prevent binding of purged buffer objects")
v2:
- Use early return for imported BOs in all four helpers to avoid
nesting (Matt B).
- Group purgeability state into a purgeable sub-struct on struct
xe_bo (Matt B).
- Reword xe_bo_willneed_put_locked() kernel-doc to explain that a 1->0
transition means all remaining active VMAs are DONTNEED (Matt B).
v3:
- Move DONTNEED/PURGED reject from vma_lock_and_validate() into
xe_vma_create(), gated on attr->purgeable_state == WILLNEED.
Fixes vm_bind bypass and partial-unbind rejection on DONTNEED
BOs (Matt B).
- Drop .check_purged from MAP and REMAP; keep it for PREFETCH and
add a comment why (Matt B).
- Skip BO validation in vma_lock_and_validate() for non-WILLNEED
VMA remnants so cleanup/remap paths do not repopulate
DONTNEED/PURGED BOs.
Suggested-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Signed-off-by: Arvind Yadav <arvind.yadav@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260506132027.2556046-1-arvind.yadav@intel.com
Signed-off-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
(cherry picked from commit 23fb2ea56c)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
cpuset_can_attach() currently adds the bandwidth of all migrating
SCHED_DEADLINE tasks to sum_migrate_dl_bw. If the source and destination
cpuset effective CPU masks do not overlap, the whole sum is then
reserved in the destination root domain.
set_cpus_allowed_dl(), however, subtracts bandwidth from the source
root domain only when the affinity change really moves the task between
root domains. A DL task can move between cpusets that are still in the
same root domain, so including that task in sum_migrate_dl_bw can reserve
destination bandwidth without a matching source-side subtraction.
Share the root-domain move test with set_cpus_allowed_dl(). Keep
nr_migrate_dl_tasks counting all migrating deadline tasks for cpuset DL
task accounting, but add to sum_migrate_dl_bw only for tasks that need a
root-domain bandwidth move. Keep using the destination cpuset effective
CPU mask and leave the broader can_attach()/attach() transaction model
unchanged.
Fixes: 2ef269ef1a ("cgroup/cpuset: Free DL BW in case can_attach() fails")
Cc: stable@vger.kernel.org # v6.10+
Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn>
Reviewed-by: Waiman Long <longman@redhat.com>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The old format to define pinctrl settings for imx in DT has two hierarchy
levels. The first level are function device nodes. The second level are
pingroups which contain a property fsl,pins. The original ntention was to
define all pin functions in a single dtsi file and just reference the
correct ones in the board files.
The commit ("5fcdf6a7ed pinctrl: imx: Allow parsing DT without function
nodes") already make moden i.MX chip support flatten layout.
Make legacy chipes (more than 15 years) support this flatten layout also.
Fixes: e948cbdc41 ("ARM: dts: imx: remove redundant intermediate node in pinmux hierarchy")
Tested-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Signed-off-by: Frank Li <Frank.Li@nxp.com>
Signed-off-by: Linus Walleij <linusw@kernel.org>
When decoding osd_state and osd_weight from an incoming osdmap in
osdmap_decode(), both are decoded for each osd, i.e., map->max_osd
times. The ceph_decode_need() check only accounts for
sizeof(*map->osd_weight) once. This can potentially result in an
out-of-bounds memory access if the incoming message is corrupted such
that the max_osd value exceeds the actual content of the osdmap message.
This patch fixes the issue by changing the corresponding part in the
ceph_decode_need() check to account for
map->max_osd*sizeof(*map->osd_weight).
Cc: stable@vger.kernel.org
Fixes: dcbc919a5d ("libceph: switch osdmap decoding to use ceph_decode_entity_addr")
Signed-off-by: Raphael Zimmer <raphael.zimmer@tu-ilmenau.de>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The receiver shutdown timer handler, batadv_tp_receiver_shutdown(), is
responsible for releasing the tp_vars reference it holds. However, the
existing logic for coordinating this release with batadv_tp_stop_all() was
flawed.
timer_shutdown_sync() guarantees the timer will not fire again after it
returns, but it returns non-zero only when the timer was pending at the
time of the call. If the timer had already expired (and
batadv_tp_stop_all() would unsucessfully try to rearm itself),
batadv_tp_stop_all() skips its batadv_tp_vars_put(), and
batadv_tp_receiver_shutdown() fails to put its own reference as well.
Fix this by introducing a new atomic variable receiving that is set to 1
when the receiver is initialized and cleared atomically with atomic_xchg()
by whichever side claims it first. Only the side that observes the
transition from 1 to 0 is responsible for releasing the tp_vars timer
reference, eliminating the uncertainty.
Cc: stable@kernel.org
Fixes: 3d3cf6a731 ("batman-adv: stop tp_meter sessions during mesh teardown")
Signed-off-by: Sven Eckelmann <sven@narfation.org>
batadv_tp_sender_shutdown() unconditionally decrements the "sending"
atomic counter. If multiple paths (e.g. timeout, user cancel, and
normal finish) call this function, the counter can underflow to -1.
Since the sender logic treats any non-zero value as "still sending",
a negative value causes the sender kthread to loop indefinitely.
This leads to a use-after-free when the interface is removed while
the zombie thread is still active.
Fix this by using atomic_xchg() to ensure the counter only transitions
from 1 to 0 once.
Fixes: 33a3bb4a33 ("batman-adv: throughput meter implementation")
Cc: stable@kernel.org
Reported-by: Yuan Tan <yuantan098@gmail.com>
Reported-by: Yifan Wu <yifanwucs@gmail.com>
Reported-by: Juefei Pu <tomapufckgml@gmail.com>
Reported-by: Xin Liu <bird@lzu.edu.cn>
Signed-off-by: Luxiao Xu <rakukuip@gmail.com>
Signed-off-by: Ren Wei <n05ec@lzu.edu.cn>
[sven: added missing change in batadv_tp_send]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
io_uring_try_cancel_requests() dropped ctx->uring_lock before calling
io_kill_timeouts(), which walks each timeout's link chain via
io_match_task() to test REQ_F_INFLIGHT. With chain mutation now
serialized by ctx->uring_lock, that walk needs the lock too.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
io_link_timeout_fn() is the hrtimer callback that fires when a linked
timeout expires. It currently calls io_remove_next_linked(prev) under
ctx->timeout_lock to splice the timeout request out of the link chain.
This is the only chain-mutation site that runs without ctx->uring_lock,
because hrtimer callbacks cannot take a mutex. Defer the splicing until
the task_work callback.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
io_wq_free_work() calls io_req_find_next() from io-wq worker context,
which reads and clears req->link without holding any lock. This can
potentially race with other paths that mutate the same chain under
ctx->uring_lock.
Take ctx->uring_lock around the io_req_find_next() call. Only requests
with IO_REQ_LINK_FLAGS reach this path, which is not the hot path.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When a controller connects, nvme_start_ctrl() emits the
"NVME_EVENT=connected" uevent and sets the NVME_CTRL_STARTED_ONCE flag.
Currently, the uevent is emitted before the flag is set. This creates a
race condition for userspace tools (like udev rules) that might rely on
the "connected" event to configure other attributes.
Swap the order of operations in nvme_start_ctrl() so that the
NVME_CTRL_STARTED_ONCE flag is set before the uevent is sent. This
guarantees that the admin_timeout can already be changed when userspace
is notified.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Since every platform driver can be forced to match a device that doesn't
match its list of device IDs because of device_match_driver_override(),
platform drivers that rely on the existence of a device's ACPI companion
object should verify its presence.
Accordingly, add requisite ACPI_COMPANION() or ACPI_HANDLE() checks
against NULL to 13 platform drivers handling core ACPI devices.
Also change the value returned by the ACPI thermal zone driver when
the device's ACPI companion is not present to -ENODEV for consistency
with the other drivers.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Hans de Goede <johannes.goede@oss.qualcomm.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/4516068.ejJDZkT8p0@rafael.j.wysocki
Cc: 7.0+ <stable@vger.kernel.org> # 7.0+
When an already-exiting task oopses, make_task_dead() currently calls
do_task_dead() with preemption enabled. That is forbidden:
do_task_dead() calls __schedule(), which has a comment saying "WARNING:
must be called with preemption disabled!".
If an oopsing task is preempted in do_task_dead(), between becoming
TASK_DEAD and entering the scheduler explicitly, bad things happen:
finish_task_switch() assumes that once the scheduler has switched away
from a TASK_DEAD task, the task can never run again and its stack is no
longer needed; but that assumption apparently doesn't hold if the dead
task was preempted (the SM_PREEMPT case).
This means that the scheduler ends up repeatedly dropping references on
the dead task's stack, which can lead to use-after-free or double-free
of the entire task stack; in other words, two tasks can end up running
on the same stack, resulting in various kinds of memory corruption.
(This does not just affect "recursively oopsing" tasks; it is enough to
oops once during task exit, for example in a file_operations::release
handler)
Fixes: 7f80a2fd7d ("exit: Stop poorly open coding do_task_dead in make_task_dead")
Cc: stable@kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yazhou Tang says:
====================
bpf: Fix call offset truncation and OOB read in bpf_patch_call_args()
From: Yazhou Tang <tangyazhou518@outlook.com>
This patchset addresses a silent truncation bug in the BPF verifier that
occurs when a bpf-to-bpf call involves a massive relative jump offset.
Additionally, it fixes a pre-existing out-of-bounds (OOB) read issue
in the interpreter fallback path.
Because the BPF instruction set utilizes a 32-bit imm field for bpf-to-bpf
calls, implicitly downcasting it to the 16-bit insn->off in bpf_patch_call_args()
causes incorrect call targets or subprog ID resolution for large BPF programs.
While fixing this by swapping the imm and off fields, it was discovered that
the original code also had a load-time OOB read vulnerability when the stack
depth exceeds MAX_BPF_STACK during JIT fallback.
Patch 1/3 fixes the pre-existing OOB read in bpf_patch_call_args(). It
changes the function to return an int and explicitly rejects the JIT
fallback if the stack depth exceeds MAX_BPF_STACK, preventing a potential
stack buffer overflow.
Patch 2/3 fixes the s16 truncation bug.
1. Keep the original imm field unchanged and use the off field to store
the interpreter function index.
2. Adjust the JMP_CALL_ARGS case in ___bpf_prog_run() accordingly.
3. Restore the legacy xlated dump layout in bpf_insn_prepare_dump().
Patch 3/3 introduces a selftest for this fix.
---
Change log:
v10:
1. Make the error log in patch 1/3 more clear. (Kuohai)
2. Drop bpftool and disasm_helpers.c changes, and instead restore the
legacy xlated dump layout in bpf_insn_prepare_dump(). This avoids
requiring bpftool compatibility handling. (Quentin and Alexei)
v9: https://lore.kernel.org/bpf/20260429171904.107244-1-tangyazhou@zju.edu.cn/
1. Modify the selftest in patch 3/3: use __clobber_all in inline asm.
(Sashiko AI reviewer)
v8: https://lore.kernel.org/bpf/20260429105608.92741-1-tangyazhou@zju.edu.cn/
1. Update cfg_partition_funcs() in bpftool to use insn->imm for call target
calculation. (Sashiko AI reviewer)
2. Modify the selftest in patch 3/3: add a large padding before the call
instruction, preventing the kernel panic on kernel without the fix.
(Sashiko AI reviewer)
3. Modify the selftest in patch 3/3: make it more clear.
v7: https://lore.kernel.org/bpf/20260421144504.823756-1-tangyazhou@zju.edu.cn/
1. Rebase the patchset to the bpf-next tree to resolve the apply conflict.
(Alexei)
2. Add Patch 1/3 to properly fix a pre-existing OOB read in bpf_patch_call_args().
(Sashiko AI reviewer)
v6: https://lore.kernel.org/bpf/20260412170334.716778-1-tangyazhou@zju.edu.cn/
1. Use a different but clearer approach to resolve this issue: keeping
the original imm field unchanged and using the off field to store the
interpreter function index. (Kuohai)
2. Update the related dumper code and remove a previous workaround in the
selftests disasm helpers, which is no longer needed after this fix.
v5: https://lore.kernel.org/bpf/20260326090133.221957-1-tangyazhou@zju.edu.cn/
1. Some minor changes in commit messages. (AI Reviewer)
v4: https://lore.kernel.org/bpf/20260326063329.10031-1-tangyazhou@zju.edu.cn/
1. Remove some redundant commit messages of patch 2/3. (Emil)
2. Change the number of instructions in padding_subprog() from 200,000
to 32,765, which is the minimum number of instructions required to
trigger the verifier failure. (Emil)
v3: https://lore.kernel.org/bpf/20260323122254.98540-1-tangyazhou@zju.edu.cn/
1. Resend to fix a typo in v2 and add "Fixes" tag. The rest of the changes
are identical to v2.
v2 (incorrect): https://lore.kernel.org/bpf/20260323081748.106603-1-tangyazhou@zju.edu.cn/
1. Move the s16 boundary check from fixup_call_args() to bpf_patch_call_args(),
and change the return type of bpf_patch_call_args() to int. (Emil)
2. Add Patch 3/3 to fix the incorrect subprog ID in dumped bpf_pseudo_call
instructions, which is caused by the same truncation issue. (Puranjay)
3. Refine the new selftest for clarity and add detailed comments explaining
the test design. (Emil)
v1: https://lore.kernel.org/bpf/20260316190220.113417-1-tangyazhou@zju.edu.cn/
====================
Link: https://patch.msgid.link/20260506094714.419842-1-tangyazhou@zju.edu.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a selftest to verify the verifier and JIT behavior when handling
bpf-to-bpf calls with relative jump offsets exceeding the s16 boundary.
The test utilizes an inline assembly block with ".rept 32765" to generate
a massive dummy subprogram. By placing this padding between the main
program and the target subprogram, it forces the verifier to process a
bpf-to-bpf call where the imm field exceeds the s16 range.
- When JIT is enabled, it asserts that the program is successfully loaded
and executes correctly to return the expected value. Since the fix
does not change the JIT behavior, the test passes whether the fix is
applied or not.
- When JIT is disabled, it also asserts that the program is successfully
loaded and executes correctly to return the expected value 3.
- Before the fix, the verifier rewrites the call instruction with a
truncated offset (here 32768 -> -32768) and lets it pass. When the
program is executed, the call instruction will go to a wrong target
(the landing pad) instead of the intended subprogram, then return -1
and fail.
- After the fix, the verifier correctly handles the large offset and
allows it to pass. The program then executes correctly to return the
expected value 3.
Co-developed-by: Tianci Cao <ziye@zju.edu.cn>
Signed-off-by: Tianci Cao <ziye@zju.edu.cn>
Co-developed-by: Shenghao Yuan <shenghaoyuan0928@163.com>
Signed-off-by: Shenghao Yuan <shenghaoyuan0928@163.com>
Signed-off-by: Yazhou Tang <tangyazhou518@outlook.com>
Acked-by: Xu Kuohai <xukuohai@huawei.com>
Link: https://lore.kernel.org/r/20260506094714.419842-4-tangyazhou@zju.edu.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Currently, the BPF instruction set allows bpf-to-bpf calls (or internal
calls, pseudo calls) to use a 32-bit imm field to represent the relative
jump offset.
However, when JIT is disabled or falls back to the interpreter, the
verifier invokes bpf_patch_call_args() to rewrite the call instruction.
In this function, the 32-bit imm is downcast to s16 and stored in the off
field.
void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth)
{
stack_depth = max_t(u32, stack_depth, 1);
insn->off = (s16) insn->imm;
insn->imm = interpreters_args[(round_up(stack_depth, 32) / 32) - 1] -
__bpf_call_base_args;
insn->code = BPF_JMP | BPF_CALL_ARGS;
}
If the original imm exceeds the s16 range (i.e., a jump offset greater
than 32767 instructions), this downcast silently truncates the offset,
resulting in an incorrect call target.
Fix this by:
1. In bpf_patch_call_args(), keeping the imm field unchanged and using the
off field to store the index of the interpreter function.
2. In ___bpf_prog_run() for the JMP_CALL_ARGS case, retrieving the
interpreter function pointer from the interpreters_args array using the
off field as the index, and passing the original imm to calculate the
last argument of the interpreter function.
After these changes, the truncation issue is resolved, and __bpf_call_base_args
is also no longer needed and can be removed, which makes the code cleaner.
Performance: In ___bpf_prog_run() for the JMP_CALL_ARGS case, changing the
retrieval of the interpreter function pointer from pointer addition to
direct array indexing improves performance. The possible reason is that the
latter has better instruction-level parallelism. See the v5 discussion [1]
for more details.
[1] https://lore.kernel.org/bpf/f120c3c4-6999-414a-b514-518bb64b4758@zju.edu.cn/
To avoid requiring bpftool changes, keep the new imm/off encoding internal
and restore the legacy xlated dump layout in bpf_insn_prepare_dump().
For bpf-to-bpf call offsets that do not fit in s16, export off as 0 instead
of a truncated and misleading value.
Fixes: 1ea47e01ad ("bpf: add support for bpf_call to interpreter")
Fixes: 7105e828c0 ("bpf: allow for correlation of maps and helpers in dump")
Suggested-by: Xu Kuohai <xukuohai@huaweicloud.com>
Suggested-by: Puranjay Mohan <puranjay@kernel.org>
Co-developed-by: Tianci Cao <ziye@zju.edu.cn>
Signed-off-by: Tianci Cao <ziye@zju.edu.cn>
Co-developed-by: Shenghao Yuan <shenghaoyuan0928@163.com>
Signed-off-by: Shenghao Yuan <shenghaoyuan0928@163.com>
Signed-off-by: Yazhou Tang <tangyazhou518@outlook.com>
Link: https://lore.kernel.org/r/20260506094714.419842-3-tangyazhou@zju.edu.cn
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
